DNA aptamers for detection of red blood cells destined for rapid post-transfusion clearance

Whole blood donations are separated into blood components by Canadian Blood Services to aid as many patients as possible. Patients whose organs are not receiving enough oxygen need red blood cell (RBC) transfusions. RBC products can be refrigerated for six weeks prior to transfusion, but older banked RBC do not last as long after transfusion as fresh RBC. Some banked RBC units, even when fresh, behave like older banked RBC. In order to better judge which units are of the highest quality, to provide the best treatment for patients, this project seeks to identify new tools to test stored RBC. In previous work the applicant and his research supervisor have identified small DNA molecules with specific sequences and shapes called aptamers. These aptamers bind to RBC fragments called microparticles (MP) or to damaged RBC called eryptotic RBC. The applicant has isolated ten aptamers from a pool of over a million billion candidates and has started to characterize them in detail. He proposes to continue this work to measure which ones bind most strongly to MP and to identify the proteins to which they bind on the MP surface. He will also use the strongest binders to see how MP numbers in RBC products increase over time of blood bank storage. In addition he will use these new quality measurement tools to understand why an active clotting factor is found on the MP surface. This research will lead to new knowledge about stored RBC products and could lead to new, inexpensive ways to test RBC to ensure their high quality, and to match the best possible product to the right patient in need of transfusion medicine care.

SHEFFIELD, William

McMaster University

Postdoctoral Fellowship Program

Ontario

$150,000